This application claims the benefit of Korean Application No. 57367/1997, filed Oct. 31, 1997, in the Korean Patent Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an inkjetting device for an inkjet printer, and more particularly, relates to an inkjetting device for continuously jetting ink drops by using a plurality of bridge and lever-type nozzle plates, which are operated by a pair of permanent magnets.
2. Description of the Related Art
Generally, the techniques applied for a conventional drop and demand-type inkjet printer head are divided into a piezo-type, a thermal-type, a continuously jetting type and so on. As shown in FIG. 1, the piezo-type has a piezoelectric element 1 to jet ink I and is used in the inkjet printer heads of the Epson company. As shown in FIGS. 2 and 3, the thermal-type has an exothermal body 2 which generates heat to jet the ink I and is used in the inkjet printer heads of the Hewlett-Packard Co., and the Canon Co., respectively. Additionally, as shown in FIG. 4, the continuously jetting type generates a magnetic force and an electrostatic force and is used in other inkjet printer heads.
As shown in FIG. 1, for generating a displacement, a driving signal is applied to the piezoelectric element 1 in the piezo-type inkjet printer head using the piezoelectric element 1. The ink is jetted by transmitting the displacement to the ink I.
As shown in FIGS. 2 and 3, when the driving signal passes through the exothermal body 2 via an electrode (not shown), the exothermal body 2, having a large resistance, generates heat in the thermal type inkjet printer head. The generated heat, which about boils the ink I, generates an air bubble in the ink I. Consequently, the generated air bubble jets the ink I from the inkjet printer head.
As shown in FIG. 4, the continuously jetting type inkjet printer head, which uses the magnetic force and the electrostatic force, has a permanent magnet 3 and a thin film coil 4 to jet the conductive ink I continuously. Accordingly, the generated magnetic force and electrostatic force by the driving signal change a moving direction of an ink drop and print the ink I onto printing paper.
In the piezo-type inkjetting method, a printing speed is low, the printer head cannot have a plurality of nozzles and a production yield is very low because the printer head is very expensive. Moreover, in the thermal-type inkjetting method, a life span of the printer head is short, resolution is lowered, compatibility of the ink is poor and the structure of the printer head is complex. In the continuously jetting type inkjetting method, the printer head consumes a large amount of ink and efficiency is lowered in spite of the fast printing speed.
Therefore, it is an object of the present invention to provide an inkjetting device for an inkjet printer having a simple structure.
It is another object of the present invention to provide an inkjetting device for an inkjet printer for reducing an amount of ink which is expended by precisely executing the inkjetting operation.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
The foregoing and other objects of the present invention are achieved by providing an inkjetting device having at least two nozzle plates arranged in a parallel line, a pair of magnets, such that a first one of the pair of magnets is formed on upper portions of the nozzle plates and a second one of the pair of magnets is formed on lower portions of the nozzle plates. Each nozzle plate includes a pair of parallel levers, which are connected to a bridge at one end portion of the nozzle plate and separated from each other at the other end portion of the nozzle plate, and a nozzle orifice formed at a front surface of the bridge, to jet ink therefrom.
In an embodiment of the present invention, each of the pair of magnets includes a permanent magnet and the polarity of the pair of magnets is determined by a direction of electric current selectively applied to the nozzle plates 102, 104, 106 and 108. Preferably, the polarity of the pair of magnets and the direction of electric current applied to the lever are determined so that force can be generated to allow the parallel pair of levers which form each nozzle plate to become closer to each other.
Moreover, preferably, both end portions of either the upper or the lower portions of the levers of each nozzle plate are fixed to one of the pair of magnets and the remaining portion of the upper or lower of the levers is spaced apart from the one magnet by a predetermined distance. Additionally, the opposite one of the upper or lower portions of the levers is spaced apart from the other magnet of the pair of magnets.
The objects of the present invention will be more clearly understood through a detailed description of the preferred embodiment and the attached drawings.